Application is made for the support of a series of eleven conferences over five years which will bring together leading national and international researcher investigators to focus on specific diagnostic issues representing some of the most pressing diagnostic issues facing the future DSM-V workgroups. This series of conferences is proposed with the following three aims in mind: 1) to promote international collaboration among important members of the scientific community in order to increase the likelihood of developing a future unified DSM/ICD; 2) to stimulate the empirical research necessary to allow informed decision making regarding crucial diagnostic deficiencies identified in DSM-IV; 3) for those disorders in which the existing DSM-IV criteria may hinder research advances, to facilitate the development of consensus criteria that could be used by the research community as an alternative to the clinical DSM criteria for future research into the etiology and pathophysiology of mental disorders. Each of the eleven conference will have three general objectives: 1) to present reviews of current data relevant to the specific diagnostic question(s) that will be the focus of the conference 2) to develop a short-term issue-focused research agenda for the design of studies that may significantly enhance the empirical data base necessary for resolving these diagnostic issues; and 3) to develop strategies to facilitate the collection of the relevant empirical data. Summaries of the research reviews, research agendas, and alternative research criteria will be disseminated to the research and clinical communities through published monographs, presentations at conferences, and posting on a DSM web site. By stimulating a systematic collaborative international effort to enrich the diagnostically-relevant research data base, we hope to facilitate the development of a more valid and ultimately unified national and international classification of mental disorders. [unreadable] [unreadable]